The present invention relates in general to the bag or package making art utilizing form, fill and seal machines, and is more particularly directed to new and improved sheet strip guide means for zippered film and method according to which plural strips of zippered material are guided into cooperative relation about a forming and filling tube in the machine.
Various and sundry mechanisms have been proposed heretofore for guiding the bag or package making sheet material, generally in the form of a plastic film, often equipped with reclosable fastener profile means, into running relation along a forming and filling tube in a form, fill and seal machine wherein successive packages are formed and filled with product contents below the lower end of the tube.
In my earlier U.S. Pat. No. 4,869,048 is disclosed a conventional forming collar about the upper end portion of the forming and filling tube by which a single sheet of material is guided into position about the tube and shaped into tubular package making form. A particular feature of that patent is in the means for stretching the tubularly shaped material to avoid wrinkling in the cross seals when forming it into successive packages.
In my earlier U.S. Pat. No. 4,790,126 there is also disclosed a zipper profile equipped single sheet guiding structure and including a tracking bar mechanism from which the tracked sheet is led to a more or less conventional forming or shaping collar or shoulder by which the sheet is guided into tubularly wrapped relation about the forming and filling tube.
Insofar as details thereof are applicable, the disclosures of the two above U.S. patents are incorporated herein by reference, so that a more streamlined description focusing on particulars of the present invention may be pursued.